1. Field of the Invention
The present invention relates to wheelchairs, and more particularly to the seat and seat supports of the wheelchair.
2. Description of the Related Art
Wheelchairs are commonly used by people who are unable to walk. The typical wheelchair has tubular metal frame with large rear wheels at each side and smaller front wheels which typically swivel. In its simplest form, the seat of the wheelchair comprises a sheet of material hung between two horizontal arms of the frame and a similar vertical sheet of material strung between two vertical posts at the rear of the wheelchair. Such sheets of material are flexible thereby conforming to the contour of the user's body.
This simple seat arrangement can aggravate certain medical conditions of some wheelchair users, especially those with spinal abnormalities or injuries. In any case, this basic seat is not very comfortable for users who sit in the wheelchair for prolonged periods of time. As a consequence, padded seats with foam cushions for the seat bottom and back have been developed. The bottom and back cushions are contoured to the general shape of the human anatomy for improved comfort. The elements of this seat are rigidly secured to the frame of the wheelchair.
Although the more elaborate seats offer increased comfort because of the foam cushions, their secure attachment to the wheelchair frame provides relatively rigid support for the user. Therefore, there still exists a need for a more comfortable wheelchair seating system, especially one that can be adjusted to the preferences of each user.